OK so let me be the first to share my experiences with my car. I have a 1990 ae91 xe corolla with the original 5afe engine and 3 speed lsd transmission. On Friday afternoon I had a very bad issue with my temperature gauge as it was randomly jumping up and down through the scale. So I parked my car at home and left it overnight so that I wouldn't run the risk of overheating. So next morning I took on the task of finding which sensors were bad. In order to do so I first had to remove the distributor to expose the sensors around the thermostat housing. In checking I found that both water temperature sending units had broken. (Will post pics of the sensors that were changed out). the next thing i did was use a degreaser and a small paintbrush to clean up the oil from the area. Then using a 12 socket i removed the first sensor unit and just let the coolant drain out. then i used a long 19 socket to get the other unit out. yes i let my coolant drain out as i had nothing to collect it with. went to the parts place and got both sensors new (sankey is the brand) for around $170 and replaced them even though it was raining. only one problem, i had forgotten to put the washer on the sensor that came off with the 19 socket so i tried to rectify the problem on sunday. my car had only been driven for a bout 10min total since the day before so i got to work on it while it was lukewarm. lo and behold when i was reinstalling the said sensor it broke from heat stress (will show pics). so now i was frantic as it had broken from hand tightening inside the thermostat housing and it was already after 12 sunday so i had very limited options as far as open parts palces. just happend to find ramai's distributors open (closed at 2) and got the new sensor for $130 (yes i had to buy one sensor twice)and so far no leaks and my temp gauge works like new.